(Checking, because I think some of the video-playing-componentry is kept down in Apple Application Support nowadays ... if there's an issue with that stuff, just uninstalling and reinstalling iTunes on its own might not clear away the trouble.)

I started having the same problem several days ago possibly after installing the latest iTunes update. The problem is still not resolved completely, but I manage to get my videos playing. So here is what worked for me: I started iTunes in safe mode (which disables any third-party plug-ins, detailed how-to is here: http://support.apple.com/kb/TS3430 ) and tried to watch a random trailer in Apple store, it worked. Then I tried to start a rented movie and iTunes crashed. I started it over in safe mode again and watched the whole movie without a problem. However, the video still doesn't run if I start iTunes normally, so we need a solution for this. Well, better than nothing

Update graphics card driver... or disable your default graphics driver. I was on the phone with Apple support on this same issue, they were not able to find any solution right now, but I did notice that when updating my video card driver, the issue was resolved

I had this same problem s a lot of others after updating to the latest I Tunes version. I finally got a decent response back from Apple, which was hard to do. Here is what they told me. Maybe it will help you:

I'm sorry to hear that you're dissatisfied with the way the episodes you purchased plays in iTunes on your computer. I appreciate your decision of contacting us to have this concern addressed. It's my pleasure to be of help for you today.

Ive Been having the same exact problem the past few weeks, Everything updated ... i even went out and picked up an apple TV last week and it connects to itunes and plays music but the video just dosent play it just keeps buffering, witch pretty much makes this useless for me. Soooo now what? and this is the most up to date post that ive found that actually has ALL the same symptoms as me. Where do i sign up to fix this!

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